New research has identified the unexplained rise of tic-like symptoms in young people since the beginning of the pandemic. Referrals for these rapid onset conditions – found almost exclusively in girls and young women – have increased from 1-5 percent of total cases pre-pandemic to 20-35 per cent of them now, according to a study published on August 13.

The researchers describe “a parallel pandemic of young people aged 12 to 25 years presenting with the rapid onset of complex motor and vocal tic-like behaviours”.

“There have been striking commonalities in the phenomenology of these tic-like behaviours observed across our centers in Canada, the United States, the United Kingdom, Germany, and Australia,” the report states.

Interestingly, the researchers observed that all patients, as well as admitting to pandemic-related stressors, “endorsed exposure to influencers on social media (mainly TikTok) with tics or Tourette’s Syndrome”. The hashtag #ticdisorder currently has over 400 million views on TikTok.

According to the researchers, “In some cases, the patients specifically identified an association between these media exposures and the onset of symptoms…. This exposure to tics or tic-like behaviours is a plausible trigger for the behaviours observed in at least some of these patients, based on a disease modeling mechanism.”

A separate article published in July, which studied popular TikTok influencers with tics, found that TikTok tics were “distinct” from those of Tourette's symptoms. “We believe this to be an example of mass sociogenic illness, which involves behaviours, emotions, or conditions spreading spontaneously through a group,” the authors concluded.

According to the report, the symptoms are different to those experienced by people with Tourette’s Syndrome, which typically begin to develop between the ages of five and seven. Referrals for these rapid onset conditions were not found in anyone younger than 11. While Tourette’s patients skew male, these referrals were nearly all girls and young women who tended to also have anxiety or a mood disorder. They also experienced more extreme symptoms than Tourette’s patients. The researchers concluded that these rapid-onset symptoms are functional tic-like behaviours, rather than tics themselves.

Unlike Tourette’s, which is genetic, researchers believe that the stress of the past year – intermittent lockdowns, social isolation, routine disruption – paired with pre-existing mental health conditions, led the patients to develop these symptoms.

According to the researchers’ theory, seeing creators with tic disorders on social media sites is the main cause of these symptoms – a form of mass sociogenic illness, previously referred to as mass hysteria. They compared their current observations to a famous 2013 outbreak of tics in Le Roy, New York, which is also thought to have been a mass sociogenic illness.

But not all researchers agree with this theory. A report published in April in the journal Archives of Disease in Childhood suggested that the role of social media has been exaggerated and that future studies can test hypotheses related to mass sociogenic illness.